> For the complete documentation index, see [llms.txt](https://docs.cleartax.in/cleartax-docs/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.cleartax.in/cleartax-docs/e-invoicing-gsp-api/e-invoicing-gsp-api-reference/sample-api.md).

# Sample API

### Base URL

```
{{HOST}}/einv-gsp
```

### Authentication

All requests require the user authentication token in the request header.

```
X-CT-Auth-Token: <YOUR-AUTH-TOKEN-HERE>
```

To generate an authentication token, please contact [ClearTax GST Sales](mailto:gst-sales@cleartax.in).

{% hint style="info" %}
You DO NOT have to add `client-id` and `client-secret` to the request headers.
{% endhint %}

### API Endpoints

#### Get Token:

```
{{HOST}}/einv-gsp/vital/v1.04/auth
```

#### Generate E-Invoice:

```
{{HOST}}/einv-gsp/core/v1.03/Invoice
```

#### Cancel E-Invoice:

```
{{HOST}}/einv-gsp/core/v1.03/Invoice/Cancel
```

#### Get E-Invoice By IRN:

```
{{HOST}}/einv-gsp/core/v1.03/Invoice/irn/{{IRN}}
```

#### Get IRN details by Doc. Details

```
{{HOST}}/einv-gsp/core/v1.03/Invoice/irnbydocdetails?doctype={{DOC_TYPE}}&docnum={{DOC_NO}}&docdate={{DOC_DATE}}
```

#### Get GSTIN Details:

```
{{HOST}}/einv-gsp/vital/v1.03/Master/gstin/{{GSTIN_NO}}
```

#### Sync GSTIN Details from CP

```
{{HOST}}/einv-gsp/vital/v1.04/Master/syncgstin/{{GSTIN_NO}}
```

#### Generate E-Waybill By IRN:

```
{{HOST}}/einv-gsp/eiewb/v1.03/ewaybill
```

#### Cancel E-Waybill:

```
{{HOST}}/einv-gsp/ewb/v1.03/ewayapi
```

#### Get EWB Details By IRN&#xD;

```
{{HOST}}/einv-gsp/eiewb/v1.03/ewaybill/irn/{{IRN}}
```

For API request/response payloads, please refer <https://einv-apisandbox.nic.in/index.html> published by NIC.&#x20;

### Error Codes

In case you have received an error code from NIC, you can check the description of the code here: \
<https://einv-apisandbox.nic.in/api-error-codes-list.html>